Device for transferring a folded box

ABSTRACT

A device for transferring a folded box from a magazine accommodating flat folded boxes to a circulating transport device thereby simultaneously erecting same, comprises a holding device transferring and carrying the folded box during transfer, and an erecting member. The holding device and the erecting member are rotatably disposed on a planetary part of a planetary gearing and are moved along a hypocycloid path having several turning points and intermediate curves. The planetary part is rotatably disposed on a planetary support which rotates about a stationary sun axis. Via a first gearing arrangement, the holding device is subjected to a superimposed, first correcting rotary motion defined along a first control curve and, via a second gearing arrangement, the erecting member is subjected to a superimposed, second correcting rotary motion defined along a second control curve. Both gearing arrangements are disposed substantially coaxially with respect to one another.

BACKGROUND OF THE INVENTION

The invention concerns a device for transferring a folded box from amagazine accommodating flat folded boxes to a circulating transportdevice while thereby simultaneously erecting same, comprising a holdingdevice transferring and carrying the folded box during transfer, and anerecting member, wherein the holding device and the erecting member arerotatably disposed on a planetary part of a planetary gearing and aremoved through a hypocycloid path having several turning points andintermediate curves, wherein the planetary part is rotatably disposed ona planetary support which rotates about a stationary sun axis.

A device of this type is used in packaging machines. Before introducingthe product to be packaged, these machines must first erect the foldedboxes, which are initially disposed in a magazine in flattened form, andintroduce same into a transport device, which is usually a band or chainconveyor. Towards this end, each folded box is removed from the magazineby a holding device which is usually a suction device disposed on acirculating planetary part of a removal device travelling about a sunwheel, and is transported together with same along a hypocycloid path tothe chain conveyor and disposed in a space defined between two carrierfingers. During movement along the hypocycloid path, an erecting memberdisposed on the planetary part is brought into abutment with the foldedbox thereby erecting it. It has turned out that use of a simpleplanetary gearing in the transferring device is insufficient toguarantee prolonged and proper transfer of the folded box to the chainconveyor. For this reason, attempts have been made to optimize thecourse of the hypocycloid path through e.g. cyclic reciprocatingmovement of the sun wheel or by adding a second sun wheel having afurther planetary part, wherein the two sun wheels are adjustablerelative to one another to thereby adjust the movements in a desiredmanner. In any event, the constructive effort is very high and thedevices are consequently not only expensive but also susceptible tofailure.

Conventionally, the holding device and the erecting member are disposednext to one another on the planetary part and are pivotableindependently of one another. As a result, the different rotationalmotions of the holding device and of the erecting member as well astheir mutual separation disadvantageously lead to relatively highdynamic loads acting on the planetary part. These loads produceirregular rotary motions, whose accommodation causes difficulties instructuring the planetary part, an increase in the amount of spacerequired, and leads to the eccentric displacement of relatively largemasses.

It is the underlying purpose of the invention to produce a device of theabove-mentioned type which has a compact construction and whichguarantees reliable transferring of the folded box to the transportdevice.

SUMMARY OF THE INVENTION

This object is achieved in a device of the above-mentioned type in thata first correcting rotary motion, defined by a first control curve, canbe superimposed upon the holding device via a first gearing arrangementand a second correcting rotary motion, defined by a second controlcurve, can be superimposed upon the erecting member via a second gearingarrangement, wherein both gearing arrangements are disposedsubstantially coaxially with respect to one another.

In accordance with the invention, correcting rotary motions are definedby one independent control curve for each rotary motion of the holdingdevice and of the erecting member, and are superimposed upon therespective rotary motion associated with rotation of the planetary part.This produces a corrected hypocycloid path which is optimally adjustedto the construction of the packaging machine.

To prevent the two gearing arrangements for the correcting rotary motionof the holding device and of the erecting member from producing largeeccentric loads on the planetary part and thereby large imbalancesduring the rotary motion, the invention provides that, to the extentpossible, the gearing arrangements are disposed coaxially with respectto each other. In this fashion, a transferring device can be producedwhich requires little space.

A preferred embodiment of the invention provides that the first gearingarrangement comprises a first correction shaft which indirectly engagesthe first control curve and which is rotated thereby and which drives,via a first gearing arrangement, a first drive shaft which iseccentrically disposed parallel thereto and which supports the holdingdevice. The second gearing arrangement also comprises a secondcorrection shaft which indirectly engages the second control curve andwhich is rotated thereby and which drives, via a second gearingarrangement, a second drive shaft which is eccentrically disposedparallel thereto and which bears the erecting member, wherein the twocorrection shafts and the two drive shafts are each coaxial with respectto one another. The coaxial arrangement of the drive shafts and of thecorrection shafts utilizes the construction space to an optimum degreeand minimizes the eccentricities and associated additional dynamic loadsof the transferring device.

The first correction shaft is preferably formed as a hollow shaftthrough which the second correction shaft penetrates. The second driveshaft may also be a hollow shaft through which the first drive shaftpenetrates.

To change or adjust the correcting rotary motion if required, the sunaxis is provided with a control disc which can preferably be replacedand in which the two control curves are formed. A further embodiment ofthe invention thereby provides that the two control curves are definedon opposing sides of the control disc to prevent mutual interference andto substantially free the course of the control curves.

Further details and features of the invention can be extracted from thefollowing description of an embodiment with reference to the drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows a vertical section through a transferring device inaccordance with the invention;

FIG. 2 shows an enlarged representation of the planetary part of thetransferring device in accordance with FIG. 1;

FIG. 3 shows first individual phases of transferring and erecting of afolded box;

FIG. 4 shows second individual phases of transferring and erecting of afolded box; and

FIG. 5 shows the course of the corrected hypocycloid path.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1 and 2 show a transferring device 1 for a folded box having astationary frame part 7 in which a sun axis 5 is fixed. A sun wheel 3 isfixedly mounted on the sun axis 5 and has a peripheral outer toothing 3a which engages with the toothing of an intermediate wheel 13. A controldisc 4 is mounted on the sun axis 5 and has a first control curve 4 a onits side facing the sun wheel 3 as well as a second control curve 4 b onits side facing away from the sun wheel 3, both of which are formed ascontinuous grooves. A planetary support 2 is rotatably disposed on thesun axis 5 via bearings 6 a, 6 b. The planetary support 2 bears theintermediate wheel 13 such that it can be rotated, surrounds the sunwheel 3 like a casing, and carries a drive wheel 8 by means of which theplanetary support 2 can be rotated about the sun axis 5.

A sleeve-like projection 11 a of a planetary part 11 is rotatablydisposed in the planetary support 2 via two axially separated bearings 2a and 2 b. As shown, in particular in FIG. 2, the sleeve-like projection11 a has a toothing 12 a on its free end facing the sun wheel 3, whichengages and runs along the outer toothing 3 a of the sun wheel 3 via theintermediate wheel 13.

A first correction shaft 16 is rotatably disposed in the sleeve-likeprojection 11 a and in the planetary part 11 via two axially separatedbearings 30 a and 30 b. The first correction shaft 16 is a hollow shaftand has a lever 32 on its rear end facing the sun wheel 3 in which afirst curve roller is rotatably disposed which runs, with closetolerance, in the first control curve 4 a of the control disc 4. Thefront end of the first correction shaft 16, facing away from the sunwheel 3, is provided with a first drive gear 17 which constitutes a sunwheel relative to the planetary support 11.

A second correction shaft 20 is rotatably disposed, via axiallyseparated bearings 31 a, 31 b, in the first correction shaft 16 andbears a yoke-shaped lever 9 passing by the control disc 4, in which asecond curve roller 10 b is rotatably disposed to run, with close.tolerance, in the second control curve 4 b formed on the rear side ofthe control disc 4. A second drive gearing 21 is disposed on the frontend of the second correction shaft 20 facing away from the sun wheel 3which also represents a sun wheel relative to the planetary support 11and which is disposed directly next to the first drive gearing 17 of thefirst correction shaft 16.

An intermediate shaft 15 is rotatably disposed in the planetary part 11via axially separated bearings 33 a, 33 b and is parallel to thesleeve-like projection 11 a and the first or second correction shaft 16,20, however displaced relative thereto. The intermediate shaft 15 bearsa first intermediate gearing 18 which engages with the first drivegearing 17 of the first correction shaft 16 as well as a secondintermediate gearing 19 which engages with the second drive gearing 21of the second correction shaft 20. The two intermediate gearings 18 and19 can be rotated relative to one another.

A second drive shaft 24 formed as hollow shaft is rotatably disposed inthe planetary part 11 and has a peripheral toothing 24 a on its oneaxial end which engages with the second intermediate gearing 19. This isnot shown in FIGS. 1 and 2 since the intermediate shaft 15 with frontgearing 14, the first intermediate gearing 18 and the secondintermediate gearing 19 are shown rotated through approximately 180° forreasons of clarity. The opposing axial end of the second drive shaft 24bears, via a holder 26, a driving rod 27 which extends in an axiallyoffset fashion and drives, via erector gearings 36, erector members 29in the form of erector levers (schematically shown in FIG. 1).

A first drive shaft 22 is rotatably disposed coaxially within the seconddrive shaft 24 via axially separated bearings 34 a and 34 b and is bornein the planetary support 11 via a bearing 35. The first drive shaft 22bears a drive gearing 23 which engages with the first intermediategearing 18 of the intermediate shaft 15. This engagement is also notvisible in FIGS. 1 and 2 since the representation is rotated, asdescribed above. The first drive shaft 22 exits the second drive shaft24 at its opposite end in the region of the holder 26 and bears aholding arm 25 in axial extension which extends substantially parallelto the drive bar 27 and bears several holding devices 28, in the form ofsuction devices, for receiving a folded box.

When the drive wheel 8 is turned, the planetary support 2 is rotatedabout the sun axis 5 wherein the gearing 12 a of the sleeve-likeprojection 11 a travels, via the intermediate gearing 13, along theouter gearing 3 a of the sun wheel 3 thereby rotating the sleeve-likeprojection 11 a and the planetary part 11. This rotates the intermediateshaft 15 with the first intermediate gearing 18 and the secondintermediate gearing 19. The first drive shaft 22 is rotated with asuitable gear ratio through engagement of the first intermediate gearing18 with the drive gearing 23 of this first drive shaft 22, therebypivoting the holding arm 25 with the suction devices 28. The seconddrive shaft 24 is rotated with a suitable gear ratio through engagementof the second intermediate gearing 19 with the gearing 24 a of thissecond drive shaft 24, thereby pivoting the drive rod 27 of the erectingmembers 29.

These rotary motions are overlapped with correcting rotary motionsextracted from the first and second control curve 4 a and 4 b of thecontrol disc 4. When the planetary support 2 turns about the sun axis 5,the first curve roller 10 a runs along the first control curve 4 a,thereby pivoting the lever 32 and the first correcting shaft 16 and thispivoting motion is transferred via the first drive gearing 17 to thefirst intermediate gearing and from same, via the drive gearing 23, tothe first drive shaft 22 and thus to the holding arm 25 of the suctiondevices 28. The second curve roller 10 b runs correspondingly along thesecond control curve 4 b which produces a pivoting motion of the secondcorrection shaft 20 via the lever 9 and thus of the second drive gearing21 which is transferred via the second intermediate gearing 19 and thetoothing of the second drive shaft 24 to the drive rod 27 of theerecting members 29.

FIG. 3 shows the basic arrangement of the transferring device within apackaging machine. The packaging machine comprises a circulating chainconveyor 43 having several carrier fingers 44 disposed at a separationfrom one another and between which gaps 45 are formed into each of whichone folded box 40 can be inserted. The chain conveyor 43 is suppliedwith folded boxes from above, wherein its supply direction F extendssubstantially horizontally. The transferring device 1 is disposed abovethe chain conveyor 43 close to its turning point. FIG. 5 shows thehypocycloid path H, centered on the sun axis 5, for the abutment surfaceof the suction devices 28 which results during drive of the planetarysupport 2 and passage through the first control curve 4 a. Thehypocycloid path H has three turning points P1, P2, P3 which lie at thecorner points of an approximately equilateral triangle. The sense ofrotation along the hypocycloid path H is substantially clock-wise asindicated by the arrows U. Since the sense of rotation of the chainconveyor 43 also extends in a clock-wise direction, the movements in thefacing neighboring sections are substantially opposite. FIG. 5 alsoillustrates a cycloid path H which would result without the correctingrotary motions produced by the control curves 4 a and 4 b.

The left upper part of FIG. 3 shows the state of the suction devices 28at the first turning point P1 at which a magazine 41 is disposedcontaining the flat folded boxes 40. The suction devices 28 areactivated in this state and grasp the lowest folded box 40 from themagazine 41. During further motion of the planetary support 2 (FIG. 4),the abutment surface of the suction devices 28 is moved together withthe folded box 40 along the first curve of the hypocycloid path H in thedirection of the second turning point P2 at which an erecting suctiondevice 42 is disposed. When the second turning point P2 has been reached(FIG. 3, top right), the folded box 40 is brought into abutment with theerecting suction device 42 thereby slightly pulling the folded box 40apart during further motion of the suction devices 28.

During movement along the second curve between the second turning pointP2 and the third turning point P3 where the folded box is handed over tothe chain conveyor 43, the suction devices 28 are additionally pivotedby 45° in the clockwise direction (FIGS. 3 and 4) such that, when theyreach the third turning point P3, their abutment surface issubstantially horizontal and they are disposed parallel to the transportdirection F of the chain conveyor 43 (FIG. 3, lower representation).During motion between the second turning point P2 and the third turningpoint P3, the erecting member 29 which forms an erection abutment, isbrought into abutment with the folded box 40 thereby completely erectingsame.

The additional pivoting motion of the suction devices 28 permitsinsertion of the folded box 40 from above into the gap 45 of thetransport device 43 formed between two carrier fingers 44, wherein theadjustment of the hypocycloid path H relative to the transport device 43has the advantage that the suction devices 28 and the folded box 40 havea component of motion in the supply direction when approaching the thirdturning point P3 where the folded box is transferred (FIG. 5). Afterdelivery of the folded box 40 to the transport device 43, the suctiondevices 28 return into the original position (FIG. 3, upper leftrepresentation) whereupon the cycle is repeated.

We claim:
 1. A device for transferring a folded box from a magazineaccommodating flat folded boxes to a circulating transport device,thereby simultaneously erecting the folded box, the transfer devicecomprising: a holding device for transferring and holding the folded boxduring transfer thereof; an erecting member for erecting the folded box;means defining a stationary sun axis; a planetary support disposed forrotation about said stationary sun axis; a planetary part disposed forrotation on said planetary support, said planetary part bearing saidholding device and said erecting member for rotation with respect tosaid planetary part to move said holding device and said erecting memberalong a hypercycloid path having several turning points and intermediatecurves; means for superimposing a first correcting rotary motion on saidholding device, said first correcting rotary motion means having meansdefining a first control curve, disposed external to said planetarypart, and a first gearing arrangement disposed between and communicatingwith said first control curve and said holding device; and means forsuperimposing a second correcting rotary motion on said erecting member,said second correcting rotary motion means having means defining asecond control curve disposed external to said planetary part and asecond gearing arrangement disposed between and communicating with saidsecond control curve and said erecting member, wherein said firstgearing arrangement and said second gearing arrangement are disposedsubstantially coaxially with respect to each other.
 2. The device ofclaim 1, wherein said first gearing arrangement comprises a firstcorrection shaft which directly follows said first control curve forrotation thereby and which drives, via a first gearing mechanism, afirst drive shaft which is disposed eccentrically and parallel to saidfirst correction shaft, said first drive shaft supporting said holdingdevice, and wherein said second gearing arrangement comprises a secondcorrection shaft which directly follows said second control curve forrotation thereby and which drives, via a second gearing mechanism, asecond drive shaft which is disposed eccentrically and parallel to saidsecond correction shaft and which bears said erecting member, whereinsaid first correction shafts extends coaxially with respect to saidsecond correction shaft and wherein said first drive shaft extendscoaxially with respect to said second drive shaft.
 3. The device ofclaim 2, wherein said first correction shaft is a hollow shaft throughwhich said second correction shaft passes.
 4. The device of claim 2,wherein said second drive shaft is a hollow shaft through which saidfirst drive shaft passes.
 5. The device of claim 1, wherein said firstcontrol curve and said second control curve are defined by a controldisc disposed on said sun axis.
 6. The device of claim 5, wherein saidfirst control curve and said second control curve are defined onopposite sides of said control disc.